It has been proposed (e.g., in U.S. Pat. No. 6,863,220) to include a user-actuatable switch in a proximity payment card. In the card proposed in the '220 patent, the switch is connected to interrupt the circuit formed by the card antenna and the card radio frequency identification (RFID) integrated circuit (IC). The switch is normally open to disable the card; when the cardholder actuates the switch, the circuit that includes the antenna and the RFID IC is completed so that the card may be activated by presenting the card to a point of sale terminal.
It may be contemplated to configure a proximity payment card with a user-actuatable switch in such a way that the switch provides an input signal to the RFID IC, rather than simply allowing the card to receive an interrogation signal. If such a switch configuration is undertaken, however, it would be advantageous to do so in a manner which minimizes the manufacturing cost for the card.